Selective B–H Amination of ortho-Carboranes Using Ammonia

  • Author: ChemistryViews.org
  • Published: 17 March 2021
  • Copyright: Wiley-VCH GmbH
  • Associated Societies: American Chemical Society (ACS), USA
thumbnail image: Selective B–H Amination of <i>ortho</i>-Carboranes Using Ammonia

Carboranes are clusters composed of boron, carbon, and hydrogen atoms. In ortho-carboranes, two neighboring vertices of the cluster cage are C–H units. They are robust and could be useful for a variety of applications. However, their stability can make functionalization reactions difficult.


Yangjian Quan, Zuowei Xie, The Chinese University of Hong Kong, China, and colleagues have developed a reaction for the selective B–H amination of ortho-carboranes using ammonia. The reaction is based on an iridium-catalyzed B–H/N–H dehydrocoupling, i.e., a reaction that formally eliminates H2 from one B–H bond of the carborane and one N–H bond of ammonia. It selectively aminates a boron atom adjacent to the two C–H vertices (product pictured). The team used [Ir(cod)OMe]2 (cod = 1,5-cyclooctadiene) as a catalyst, PCy3 as a ligand (Cy = cyclohexyl), K2CO3 as a base, and tetrahydrofuran (THF) as the solvent to aminate a variety of C- or B-substituted ortho-carboranes using NH3.


The desired products were obtained in moderate to good yields. The reaction uses cheap ammonia gas as a reactant and produces H2 as the only byproduct. According to the researchers, the work provides a new pathway for the direct, efficient, and regioselective B–H amination of ortho-carboranes.


 

 

Article Views: 5948

Sign in Area

Please sign in below

Additional Sign In options

Please note that to comment on an article you must be registered and logged in.
Registration is for free, you may already be registered to receive, e.g., the newsletter. When you register on this website, please ensure you view our terms and conditions. All comments are subject to moderation.

Article Comments - To add a comment please sign in

If you would like to reuse any content, in print or online, from ChemistryViews.org, please contact us first for permission and consult our permission guidance prior to making your request

Follow on Facebook Follow on Twitter Follow on YouTube Follow on LinkedIn Follow on Instagram RSS Sign up for newsletters

Magazine of Chemistry Europe (16 European Chemical Societies) published by Wiley-VCH